1. Field of the invention
This invention relates to an electric connecting device wherein electric connection between a fixed member and a movable member mounted for rotation relative to the fixed member is established by means of a cable such as a flat cable.
2. Description of the Prior Art
An electric connecting device for electrically connecting a fixed member and a movable member to each other is used, for example, for a steering wheel of an automobile. In such an arrangement, it is necessary to mount the electric connecting device such that the movable member can be rotated by a substantially equal amount in the opposite directions from a neutral position of the steering wheel. An electric connecting device which is conventionally used is provided with a mechanism which presents an index for positioning between a fixed member and a movable member in order to attain such rotational movement of the movable member as described above. A conventional positioning mechanism of the type mentioned normally includes a rotatable member provided on either the fixed member or the movable member and having a gear thereon, and an engaging member provided on the other member for engaging with the gear of the rotatable member. Each time the movable member makes one rotation, the gear is engaged with and rotated by a predetermined angle by the engaging member. Accordingly, when a particular tooth of the gear is positioned at a predetermined position and the movable member is positioned at a predetermined position with respect to the fixed member, the steering wheel assumes its neutral position. Thus, a mark is applied to the particular tooth of the gear and also to a member on which the gear is supported while a mark is applied to both of the movable member and the fixed member, and in assembling the electric connecting device to an appliance, the marks are positioned in a mutually aligned relationship in order to assemble the electric connecting device in a condition wherein the movable member assumes its neutral position with respect to the fixed member.
An electric connecting device is also known wherein a clip member is provided on a locking member mounted on a rotatable member. The clip member is engaged by a snap action with an engaging portion formed on a fixed member in order to hold a movable member at its neutral position with respect to the fixed member before an assembly composed of the movable member and the fixed member is assembled to a predetermined appliance, and after completion of the assembly to the appliance, the locking member is removed from the fixed member.
By the way, such a locking member as mentioned above is formed from a hard material such as a plastic material. Accordingly, if the locking member is left in engagement with the fixed member after assembly of the electric connecting device to the appliance, then the movable member cannot be rotated. In such an instance, if the movable member is forced to rotate after assembly, a portion of the fixed member remaining in engagement with the locking member may be broken, causing a fragment of the fixed member to remain within the casing and to make undesirable noises upon driving of the automobile.
Further, in assembling the above described electric connecting device to an appliance, it may be mounted and removed several times repetitively due to a relationship thereof to some other members which are to be assembled together with the electric connecting device. It is cumbersome, however, to mount and remove the locking member each time the electric connecting device is mounted and removed. Therefore, after the locking member is once removed, a re-mounting operation is conducted without re-mounting the locking first member. Accordingly, even if the movable member is assembled while it is positioned accurately with respect to the fixed member upon re-mounting of the locking member after removal, there is the possibility that the movable member may be displaced out of position in the course of assembly. Also there is a drawback that the ease of assembly is low.